RTT bugfixes, part 5

* Add a new API to allow Telecom to inform ConnectionServices when the
RTT text stream changes
* No longer set the RTT property from ConnectionService. Client apps
should be setting properties themselves.
* Add Dialer-side RTT property in order to remove the dependence on
checking the RTT streams, which have a complex lifecycle

Bug: 72951201
Bug: 72648661
Test: manual, with real RTT calls and Dialer's SimulatorConnection, also
cts
Change-Id: Ic4c7d883d2dc6baf8e8c0eaa4df58d7de8762b9e
Merged-In: Ic4c7d883d2dc6baf8e8c0eaa4df58d7de8762b9e

telecomm/java/android/telecom/ConnectionRequest.java

@@ -143,6 +143,8 @@ public final class ConnectionRequest implements Parcelable {
     private final boolean mShouldShowIncomingCallUi;
     private final ParcelFileDescriptor mRttPipeToInCall;
     private final ParcelFileDescriptor mRttPipeFromInCall;
+    // Cached return value of getRttTextStream -- we don't want to wrap it more than once.
+    private Connection.RttTextStream mRttTextStream;
 
     /**
      * @param accountHandle The accountHandle which should be used to place the call.
@@ -312,7 +314,10 @@ public final class ConnectionRequest implements Parcelable {
      */
     public Connection.RttTextStream getRttTextStream() {
         if (isRequestingRtt()) {
-            return new Connection.RttTextStream(mRttPipeToInCall, mRttPipeFromInCall);
+            if (mRttTextStream == null) {
+                mRttTextStream = new Connection.RttTextStream(mRttPipeToInCall, mRttPipeFromInCall);
+            }
+            return mRttTextStream;
         } else {
             return null;
         }